Carbonate and carbamate modified forms of glucocorticoids in combination with β2 adrenergic agonists

ABSTRACT

Compositions containing β 2  adrenergic agonists in combination with carbonates and carbonates of the formula 
                         
and in combination with related steroid carbonates and carbonates are disclosed. The compositions are useful for treating bronchospasm, for inducing bronchodilator and for treating rhinitis, asthma, and chronic obstructive pulmonary disease (COPD) and inflammatory diseases, particularly by inhalation.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/364,659 filed Feb. 28, 2006, now U.S. Pat. No. 7,253,156 which is acontinuation of U.S. patent application Ser. No. 10/633,086 filed Aug.1, 2003, now abandoned, which is a continuation in part of U.S. patentapplication Ser. No. 10/369,828 filed Feb. 20, 2003, now U.S. Pat. No.7,018,995, which claims the priorities of US provisional applications60/358,246, filed Feb. 20, 2002, and 60/428,180, filed Nov. 21, 2002.The entire disclosures of all of the prior applications and patents areincorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to methods of treating rhinitis, asthma, andinflammation using carbonate and carbamate derivatives ofglucocorticoids in combination with β₂ adrenergic agonists.

BACKGROUND OF THE INVENTION

Glucocorticoids, in topical, oral and inhaled formulations, are usefulfor their anti-inflammatory and immunosuppressive activities.Notwithstanding the sophistication of many formulations, manyglucocorticoids exhibit significant side-effects that preventrealization of their maximum pharmacologic value. These side-effectsstem, in part, from the difficulty of effectively delivering theglucocorticoid drug to a target tissue without increasing systemicconcentrations of the drug.

Inhaled glucocorticoids are an effective therapy for the control ofasthma, and improvement with steroids is one of the hallmarks of asthma[Barnes, P J (1998) in Asthma: Basic Mechanisms and Clinical Management(3^(rd) ed)]. The inhaled glucocorticoids work to reduce theinflammation in either lungs, e.g. for asthma, or nose, e.g. for nasalallergies. Inhaled glucocorticoids are most often administered using ametered dose inhaler (MDI). In the best of circumstances, in controlledclinical settings, only around 30% of the administered dose gets intothe lungs. In the general patient population probably only 10% or so ofthe dose gets into the lungs due to improper use of the inhaler. Therest of the administered drug is deposited in the throat and upperairways, or is swallowed. The drug that is deposited in the throat isresponsible for some side effects seen with inhaled glucocorticoids(cough, oropharyngeal candidiasis and dysphonia). For early generationinhaled glucocorticoids, the swallowed drug leads to the same sideeffects seen with oral glucocorticoids. In light of the tremendousefficacy of inhaled glucocorticoids in asthma, much effort has gone intoreducing the side effects from their use. Although newer glucocorticoids(e.g. budesonide, ciclesonide, triamcinolone and fluticasone) exhibitreduced systemic side effects from the swallowed drug—being eitherpoorly absorbed in the gut or subject to extensive inactivation in theliver—they nonetheless display systemic side effects as a result ofabsorption from the lung into the systemic circulation. The side effectsinclude decreased bone density (Israel, E et al., (2001), New EnglandJournal of Medicine 345:941-947 and Wong, C A et al., (2000) Lancet355:1399-1403), which has been correlated with increased risk offracture. Thus the need still exists for inhaled glucocorticoids withreduced systemic effects.

Several approaches have been suggested to reduce systemic effects. Onesuch approach takes advantage of inactive prodrugs that are activated inthe lung tissues. For example, Dietzel et al. [Prog. Respir Res. 31,91-93 (2001)] have described an isopropyl group esterified at the 21position of the glucocorticoid core structure. Another approach that hasbeen suggested is the formulation of a glucocorticoid as a liposome.Axelsson et al. in a series of U.S. Pat. Nos. 4,693,999; 5,614,514 and5,888,995 describe selected glucocorticoids modified for formulationinto liposomes by esterification at the 21 position with saturated andmono-unsaturated fatty acids with chain lengths up to 20 carbons.

SUMMARY OF THE INVENTION

It has now been found that by combining the following carbonate andcarbamate compounds of Formula I:

with β₂ adrenergic agonists, novel drug formulations effective intreating asthma and rhinitis, as well as other respiratory andinflammatory conditions are provided. Furthermore, the new drugcompositions provide unexpectedly greater potency for an extended periodof time relative to known glucocorticoid alcohols or shorter chaincarbonates and carbamates.

In the compounds of Formula I according to the invention:

-   -   R¹ and R², independently for each occurrence, represent a        hydrogen, lower alkyl or lower acyl, or taken together R¹ and R²        form a substituted or unsubstituted ketal;    -   R³ is —OR⁴ or —NR⁵R⁶;    -   R⁴ is chosen from C₇ to C₂₄ hydrocarbon, —(C₇ to C₂₄        hydrocarbon)—COOH and —(C₇ to C₂₄ hydrocarbon)—NR⁹R¹⁰;    -   R⁵ is hydrogen or C₇ to C₂₄ hydrocarbon;    -   R⁶ is chosen from C₇ to C₂₄ hydrocarbon and —(C₇ to C₂₄        hydrocarbon)—COOH;    -   R⁹ is hydrogen or C₁ to C₁₇ hydrocarbon;    -   R¹⁰ is hydrogen or C₁ to C₁₇ hydrocarbon;    -   R¹¹ is methyl or —OR²; and    -   X and Y are independently hydrogen or halogen.

Therefore, in one aspect, the invention relates to pharmaceuticalcompositions comprising the compounds of Formula I in combination withβ₂ adrenergic agonists.

In another aspect the invention relates to methods for treatingbronchospasm, for inducing bronchodilation and for treating rhinitis,asthma, and chronic obstructive pulmonary disease (COPD) andinflammatory diseases and conditions, which comprise administering thecompositions containing a compound of Formula I in combination with a β₂adrenergic agonist.

In another aspect, the invention relates to pharmaceutical formulationsfor inhalation comprising the compositions containing a compound ofFormula I in combination with a β₂ adrenergic agonist, apharmaceutically acceptable fluid for suspension or solution, and, formetered dose inhalers, additionally comprising a propellant.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph of the percent reduction in rat paw edema as afunction of the number of carbons in a series of carbamate esters ofbudesonide.

FIG. 2 is a graph of the percent reduction in rat paw edema as afunction of the dose of budesonide at four time intervals.

FIG. 3 is a graph of the percent reduction in rat paw edema as afunction of the dose of budesonide dodecylcarbonate at four timeintervals.

DETAILED DESCRIPTION OF THE INVENTION

The invention relates to compositions obtained by combining β₂adrenergic agonists with compounds of Formula I:

in which the substituents are as defined above. In preferred embodimentsthe steroid of Formula I has the absolute stereochemistry shown:

Examples of steroids having the foregoing structure include budesonide,ciclesonide and triamcinolone. The most preferred embodiment of FormulaI compounds have structure:

wherein R⁷ is hydrogen or lower alkyl; and R⁸ is lower alkyl. Inparticularly preferred embodiments, R⁴ is C₁₁ to C₁₄ alkyl, C₁₂to C₂₄alkyl, C₁₂ to C₂₀ alkyl, C₇ to C₂₄ alkyl, C₈ to C₂₄ alkyl, C₉to C₂₄alkyl, C₁₀ to C₂₄ alkyl, C₁₁ to C₂₄ alkyl, C₈to C₁₈ alkyl, C₁₀ to C₁₆alkyl or C₈ to C₂₀ alkyl. In preferred embodiments the steroid isbudesonide, ciclesonide or triamcinolone. Budesonide dodecyl carbonateis most preferred.

In embodiments of Formula I in which R³ is —OR⁴ and R⁴ is —(C₇ to C₂₄hydrocarbon)—NR⁹R¹⁰, it is preferred that the total number of carbons inR³ be eight to twenty-four. Similarly, in embodiments in which R³ is—NR⁵R⁶, it is preferred that the sum of the number of carbons in R⁵ plusthe number of carbons in R⁶ be seven to twenty-four. The underlyingguideline is that the total number of carbons in the residue R³ isoptimally seven to twenty-four, but an amino function could beinterposed at any point that results in an R³ residue that is chemicallystable in combination with the adjacent O(C═O) residue.

In another particularly preferred embodiment of Formula I, R³ is

and R⁶ is C₁₁ to C₁₄ alkyl, C₁₂ to C₂₄ alkyl, C₁₂ to C₂₀ alkyl, C₇ toC₂₄ alkyl, C₈ to C₂₄ alkyl, C₉to C₂₄ alkyl, C₁₀ to C₂₄ alkyl, C₁₁ to C₂₄alkyl, C₈to C₁₈ alkyl, C₁₀ to C₁₆ alkyl or C₈ to C₂₀ alkyl.

As used herein, alkyl is intended to include linear, branched, or cyclichydrocarbon structures and combinations thereof. Preferred alkyl groupsare those of C₇ to C₂₄. Cycloalkyl is a subset of alkyl and includescyclic hydrocarbon groups, in this case preferably from 6 to 8 carbonatoms. Lower acyl is acyl of one to six carbons, e.g. acetyl, propionyl,isopropanoyl, butanoyl, sec-butanoyl, valeroyl, and hexanoyl.

C₇ to C₂₄ Hydrocarbon includes alkyl, cycloalkyl, alkenyl, alkynyl, aryland combinations thereof. Examples include phenethyl, cyclohexylmethyl,camphoryl and naphthylethyl.

The β₂ adrenergic agonists included in the present compositions asactive ingredients with Formula I compounds are non-steroidalbronchodilators or inhibitors of bronchospasm that act selectively onthe β₂ adrenergic receptors. Exemplary useful β₂ adrenergic agonistsinclude, but are not limited to, the following drug substances:terbutaline, albuterol (also known as salbutamol), fenoterol,hexoprenaline, rimiterol, isoetharine, orciprenaline, metaproterenol,reproterol, clenbuterol, procaterol, carbuterol, tulobuterol,pirbuterol, and bitolterol. Also included are the long acting selectiveβ₂ adrenergic agonists, such as, formoterol, bambuterol, salmeterol,[(R,S)-1-(4-hydroxy-3-hydroxymethylphenyl)-2-[6-(4-phenylbutoxy)hexylamino]ethanol].In addition, the acid salts of the aforementioned β₂ agonists areincluded, as well as the analogs and mixtures thereof. All of the abovelisted β₂ adrenergic agonists are commercially available.

The compounds of Formula I described herein, as well as the β₂adrenergic agonists, contain one or more asymmetric centers and may thusgive rise to enantiomers, diastereomers, and other stereoisomeric formsthat may be defined, in terms of absolute stereochemistry, as (R)— or(S)—. The present invention is meant to include all such possibleisomers, as well as, their racemic and optically pure forms. Opticallyactive isomers may be prepared using chiral synthons or chiral reagents,or resolved using conventional techniques. When the compounds describedherein contain olefinic double bonds or other centers of geometricasymmetry, and unless specified otherwise, it is intended that thecompounds include both E and Z geometric isomers. Likewise, alltautomeric forms are also intended to be included. The graphicrepresentations of racemic, ambiscalemic and scalemic orenantiomerically pure compounds used herein are taken from Maehr J.Chem. Ed. 62, 114-120 (1985): solid and broken wedges are used to denotethe absolute configuration of a chiral element; wavy lines indicatedisavowal of any stereochemical implication which the bond it representscould generate; solid and broken bold lines are geometric descriptorsindicating the relative configuration shown but denoting racemiccharacter; and wedge outlines and dotted or broken lines denoteenantiomerically pure compounds of indeterminate absolute configuration.

The abbreviations Me, Et, Ph, Tf, Ts and Ms represent methyl, ethyl,phenyl, trifluoromethanesulfonyl, toluensulfonyl and methanesulfonylrespectively. A comprehensive list of abbreviations utilized by organicchemists (i.e. persons of ordinary skill in the art) appears in thefirst issue of each volume of the Journal of Organic Chemistry. Thelist, which is typically presented in a table entitled “Standard List ofAbbreviations” is incorporated herein by reference.

The term “methods of treating” when used in connection with the presentinvention means amelioration, prevention or relief from the symptomsand/or effects associated with asthma and rhinitis. The person ofordinary skill in the medical art recognizes that “prevention” of thesymptoms and/or effects associated with asthma and rhinitis is not anabsolute term. In the medical art it is understood to refer to theprophylactic administration of a drug to substantially diminish thelikelihood or seriousness of the condition.

The compositions of the present invention, which include Formula Icompounds in combination with β₂ adrenergic agonists, are useful fortreating COPD, asthma, and rhinitis, as well as for treatinginflammatory and other respiratory conditions. For administration, adose providing a weight ratio of Formula I compound to β₂ adrenergicagonist ranging from 1:6 to 6:1, but more typically 1:1, is generallytherapeutically effective.

In general, the compounds having Formula I may be prepared by themethods illustrated in the general reaction schemes as, for example,described below, or by modifications thereof, using readily availablestarting materials, reagents and conventional synthesis procedures. Inthese reactions, it is also possible to make use of variants that are inthemselves known, but are not mentioned here.

Exemplary syntheses of a budesonide carbonate and a carbamate are shownin Schemes 1 and 2. One skilled in the art will recognize that thesyntheses can be adapted to prepare a variety of carbonate or carbamatemodified budesonide, ciclesonide, fluticasone or triamcinolone analogs.

Synthesis of Budesonide Dodecylcarbonate. (Example 2)

To the solution of budesonide (750 mg, 1.74 mmol) in DCM (7.5 mL) wasadded dodecyl chloroformate (513 mL, 1.617 mmol) and Et₃N (533 μL, 3.825mmol) at room temperature. The reaction mixture was stirred at roomtemperature for 7 hours. During this 7 hours more dodecyl chloroformate(510 μL, 1.616 mmol) and Et₃N (440 μL, 3.18 mmol) were added. Thereaction was followed by HPLC. The reaction mixture was poured intowater (20 mL) and DCM (10 mL); the aqueous phase was extracted with DCM(10 mL). The combined organic phases were washed with water (10 mL) andbrine (10 mL), dried over Na₂SO₄, filtered, and concentrated in vacuo toprovide crude budesonide dodecylcarbonate. The product was purified bychromatography, eluted with Hexane: AcOEt=9:1 to 3:1 to provide 983 mgof 1:1 mixture of epimers (originated from budesonide) (96.78 area %purity on HPLC). ¹H NMR (CDCl₃) δ 0.80-2.25 (m, 45H), 2.36 (d, 1H, 13.4Hz), 2.58 (t, 1H, 13.2 Hz), 4.19 (t, 2H, 6.7 Hz), 4.52 (bs, 1H), 4.6-5.2(m, 5H), 6.03 (s, 1H), 6.30 (d, 1H, 10.1 Hz), 7.29 (d, 1H, 10.1 Hz). ¹³CNMR (CDCl₃) δ 14.21, 14.38, 17.22, 17.35, 17.50, 17.78, 21.35, 22.94,25.86, 28.83, 29.45, 29.60, 29.74, 29.80, 29.88, 30.57, 31.24, 32.16,33.18, 33.68, 34.26, 35.26, 37.36, 41.17, 41.41, 44.24, 46.18, 47.61,50.01, 53.14, 55.41, 55.52, 69.12, 69.18, 70.11, 70.22, 82.32, 83.57,97.76, 98.62, 104.88, 108.63, 122.83, 128.24, 156.14, 169.81, 169.92,186.74, 202.16 and 203.46. Mass spectrum (m/e) 643 (M⁺).

Synthesis of Budesonide Hexadecylcarbonate. (Example 7)

To the solution of budesonide (431 mg, 1.0 mmol) in DCM (4.5 mL) wasadded heaxdecyl chloroformate (655 μL, 2.0 mmol) and Et₃N (512 μL, 3.7mmol) at room temperature. After reaction mixture was stirred at roomtemperature over night, it was poured into water (20 mL) and DCM (10mL); the aqueous phase was extracted with DCM (10 mL). The combinedorganic phases were washed with water (10 mL) and brine (10 mL), driedover Na₂SO₄, filtered, and concentrated in vacuo to provide crudebudesonide hexadecylcarbonate. The product was purified bychromatography, eluted with Hexane: AcOEt=9:1 to 3:1 to provide 432 mgof 1:1 mixture of epimers (originated from budesonide) (99.38 area %purity on HPLC). ¹H NMR (CDCl₃) δ 0.80-2.40 (m, 53H), 2.56 (dt, 1H, 13.1and 4.6 Hz), 4.30 (t, 2H, 6.7 Hz), 4.5-5.2 (m, 7H), 6.00 (s, 1H), 6.26(d, 1H, 10.1 Hz), 7.3 (d, 1H, 10.1 Hz). ³C NMR (CDCl₃) δ 14.16, 14.18,14.34, 17.10, 17.27, 17.39, 17.71, 21.21, 22.88, 25.81, 28.79, 29.41,29.56, 29.70, 29.76, 29.87, 30.54, 31.19, 32.11, 33.08, 33.59, 34.23,35.19, 37.28, 40.68, 40.98, 44.37, 46.08, 47.52, 50.00, 53.07, 55.39,55.49, 68.98, 69.73, 69.83, 69.95, 70.04, 82.10, 83.38, 97.71, 98.58,104.70, 108.51, 122.57, 127.91, 155.08, 156.85, 170.48, 170.59, 186.84,186.88, 202.10 and 203.38. Mass spectrum (m/e) 699 (M⁺).

Synthesis of Budesonide Decylcarbonate. (Example 8)

To the solution of budesonide (431 mg, 1.0 mmol) in DCM (4.5 mL) wasadded decyl chloroformate (460 μL, 2.0 mmol) and Et₃N (512 μL, 3.7 mmol)at room temperature. After the reaction mixture was stirred at roomtemperature over night, it was poured into water (20 mL) and DCM (10mL); the aqueous phase was extracted with DCM (10 mL). The combinedorganic phases were washed with water (10 mL) and brine (10 mL), driedover Na₂SO₄, filtered, and concentrated in vacuo to provide crudebudesonide decylcarbonate. The product was purified by chromatography,eluted with Hexane: AcOEt=9:1 to 3:1 to provide 348 mg of 1:1 mixture ofepimers (originated from budesonide) (99.22 area % purity on HPLC). ¹HNMR (CDCl₃) δ 0.85-2.24 (m, 42H), 2.36 (dd, 1H, 13.4 and 2.9 Hz), 2.59(dt, 1H, 13.5 and 4.5 Hz), 4.18 (t, 1H, 6.7 Hz), 4.51 (s, 1H), 4.6-5.2(m, 5H), 6.03 (s, 1H), 6.30 (d, 1H, 10.1 Hz), 7.49 (d, 1H, 10.1 Hz). ¹³CNMR (CDCl₃) δ 14.14, 14.17, 14.31, 17.06, 17.24, 17.36, 17.68, 21.19,22.83, 25.78, 28.76, 29.37, 29.40, 29.66, 30.52, 31.16, 32.04, 33.05,33.56, 34.22, 35.16, 37.25, 40.58, 40.89, 44.38, 46.06, 47.49, 49.98,53.05, 55.38, 55.48, 68.90, 68.94, 69.65, 69.75, 69.92, 70.01, 82.05,83.34, 97.69, 98.56, 104.65, 108.47, 122.51, 127.84, 155.04, 156.96,170.61, 170.71, 186.84, 186.89, 202.08 and 203.37. Mass spectrum (m/e)615 (M⁺).

Synthesis of Budesonide Butylcarbamate. (Example 6)

To the solution of budesonide (500 mg, 1.16 mmol) in DCM (5.0 mL) wasadded butyl isocyanate (144 μL, 1.28 mmol) and DMAP (312 mg, 2.55 mmol)at room temperature. The reaction mixture was stirred at roomtemperature for 24 hours. During this 24 hours more butyl isocyanate (72μL, 0.64 mmol) and DMAP (156 mg, 1.27 mmol). The reaction was followedby HPLC. The reaction mixture was poured into water (20 mL) and DCM (10mL); the aqueous phase was extracted with DCM (10 mL). The combinedorganic phases were washed with water (10 mL) and brine (10 mL), driedover Na₂SO₄, filtered, and concentrated in vacuo to provide crudebudesonide butylcarbamate. The product was purified by chromatography,eluted with Hexane: AcOEt=9:1 to 3:1 to provide 560 mg of 1:1 mixture ofepimers (originated from budesonide) (99.22 area % purity on HPLC). ¹HNMR (CDCl₃) δ 0.82-2.7 (m, 30H), 3.06-3.20 (m, 3H), 4.45 (m, 1H), 4.58(t, 1H, 4.5 Hz), 4.75-5.36 (m, 5H), 5.99 (s, 1H), 6.24 (d, 1H, 10.1 Hz),7.29 (d, 1H, 10.1 Hz). ¹³C NMR (CDCl₃) δ 13.98, 14.08,14.22, 17.09,17.30, 17.37, 17.73, 20.09, 20.28, 21.26, 30.56, 31.22, 32.11, 32.59,33.13, 33.65, 34.27, 35.23, 37.34, 40.30, 40.73, 40.99, 41.17, 44.37,46,09, 47.49, 50.01, 53.15, 55.43, 55.52, 67.82, 69.82, 69.93, 82.11,83.37, 97.84, 98.75, 104.66, 108.43, 122.61, 127.97, 155.94, 156.03,156.79, 170.45, 170.56, 186.95, 203.89 and 205.21.

Synthesis of Budesonide 2-Dimethylaminoethyl Carbonate. (Example 20)

To the solution of budesonide (600 mg, 1.394 mmol) in DCM (5.0 mL) wasadded CDI (249 mg, 1.53 mmol) at RT. After 3 hr stirring,N,N-dimethylethanolamine (308 μL, 3.07 mmol) was added at roomtemperature. After the reaction mixture was stirred at room temperaturefor 3.5 hours, it was poured into water (20 mL) and DCM (10 mL); theaqueous phase was extracted with DCM (10 mL). The combined organicphases were washed with water (10 mL) and brine (10 mL), dried overNa₂SO₄, filtered, and concentrated in vacuo to provide crude budesonide2-dimethylaminoethyl carbonate. The product was purified bychromatography, eluted with AcOEt, then AcOEt: MeOH=98:2 to 95:5 toprovide 307 mg of 1:1 mixture of epimers (originated from budesonide)(98.49 area % purity on HPLC). ¹H NMR (CDCl₃) δ 0.80-2.55 (m, 29H), 3.69(bs, 1H), 4.17 (t, 2H, 5.8 Hz), 4.42 (bs, 1H), 4.4-4.95 (m, 3H), 5.05(dd, 1H, 12.5 and 7.2 Hz), 5.92 (s, 1H), 6.28 (d, 1H, 10.1 Hz), 7.29 (d,1H, 10.1 Hz). ¹³C NMR (CDCl₃) δ 14.16, 14.21, 17.08, 17.20, 17.37,17.69, 21.22, 30.52, 31.18, 32.10, 33.06, 33.60, 34.28, 35.16, 37.24,40.65, 40.94, 44.46, 45.86, 46.23, 47.64, 49.99, 53.11, 55.36, 55.45,57.56, 66.27, 66.30, 69.34, 69.45, 70.14, 70.18, 82.14, 83.41, 97.76,98.62, 104.64, 108.42, 122.48, 127.73, 154.92, 157.26, 157.37, 170.75,170.89, 187.00, 187.08, 201.97 and 203.29.

The following compounds were synthesized as described above:

Example Name mol. Wt. 1 Budesonide isobutylcarbonate 530.65 2 Budesonidedodecylcarbonate 642.87 3 Budesonide hexylcarbonate 558.71 4 Budesonidedibutylcarbamate 585.77 5 Dexamethasone dodecylcarbonate 604.8 6Budesonide butylcarbamate 529.67 7 Budesonide hexadecylcarbonate 698.988 Budesonide decylcarbonate 614.81 9 Budesonide hexylcarbonate 558.71 10Budesonide dodecylcarbonate 642.86 11 Budesonide nonylcarbonate 600.7812 Budesonide octycarbonate 586.76 13 Budesonide undecylcarbamate 627.8514 Budesonide heptylcarbonate 572.73 15 Budesonide11-dimethylaminoundecylcarbonate 671.9 16 Budesonide phytolcarbonate753.07 17 Budesonide farnesolcarbonate 678.90 18 Budesonidegeraniolcarbonate 610.78 19 Budesonide nerolcarbonate 610.78

For administration to treat asthma, rhinitis, COPD and respiratoryconditions, the drug of Formula I in combination with one or more β₂agonists, is suitably inhaled from a nebulizer, from a pressurizedmetered dose inhaler or as a dry powder from a dry powder inhaler (e.g.sold as TURBUHALER®) or from a dry powder inhaler utilizing gelatin,plastic or other capsules, cartridges or blister packs.

A diluent or carrier, generally non-toxic and chemically inert to themedicaments, e.g. lactose, dextran, mannitol or glucose or any additivesthat will give the medicaments a desired taste, can be added to thepowdered medicaments.

For drugs such as β₂ adrenergic agonists to be absorbed by the alveoliof the lungs, the particle size of the drug is normally reduced to lessthan about 10 micrometers, preferably between about 0.5 micrometers andabout 5 micrometers.

Formulations and devices for nebulizers, metered dose inhalers and drypowder inhalers are well known to those skilled in the art. Informulations where the active ingredients are in a suspension, it isimportant that the particles be below 20 μm in size and preferably below5 μm in size. This may be achieved by micronization, crystallization,spray drying or other known techniques.

The solvent or suspension agent utilized for nebulization may be anypharmacologically suitable fluid such as water, aqueous saline, alcoholsor glycols, e.g., ethanol, isopropylalcohol, glycerol, propylene glycol,polyethylene glycol, etc. or mixtures thereof. Saline solutions utilizesalts which display little or no pharmacological activity afteradministration. Both inorganic salts, such as alkali metal or ammoniumhalogen salts e.g. sodium chloride, potassium chloride or organic salts,such as potassium, sodium and ammonium salts of organic acids, e.g.,ascorbic acid, citric acid, acetic acid, tartaric acid, etc. may be usedfor this purpose.

Other excipients and additives may be added to the formulation. Theactive ingredients may be stabilized by the addition of an inorganicacid, e.g., hydrochloric acid, nitric acid, sulphuric acid and/orphosphoric acid; an organic acid, e.g., ascorbic acid, citric acid,acetic acid, and tartaric acid etc.; a complexing agent such as EDTA orcitric acid and salts thereof; or an antioxidant such as vitamin E orascorbic acid. These may be used alone or together to stabilize theactive ingredients. Preservatives can also be added such as benzalkoniumchloride or benzoic acid and salts thereof. Surfactant may be addedparticularly to improve the physical stability of suspensions. Theseinclude lecithins, disodium dioctylsulphosuccinate, oleic acid andsorbitan esters.

The active ingredients may also be suspended or dissolved in a liquifiedpropellant, sealed in a container with a metering valve and fitted intoan actuator. Such metered dose inhalers are well known in the art. Themetering valve may meter 10 to 500 μL and preferably 25 to 150 μL.

The propellants used may be halocarbons, hydrocarbons or other liquifiedgasses. The most frequently used are trichlorofluoromethane (propellant11), dichlorofluoromethane (propellant 12), dichlorotetrafluoroethane(propellant 114), tetrafluoroethane (HFA-134a), 1,1-difluoroethane(HFA-152a), difluoromethane (HFA-32), pentafluoroethane (HFA-125),heptafluoropropane (HFA-227ea), perfluoropropane, perfluorobutane,perfluorpentane, butane, isobutane, and pentane. In particular,tetrafluoroethane (HFA-134a) and heptafluoropropane (HFA-227ea) andmixtures thereof are used.

As well as propellant, formulations may contain other excipients.Surfactant may be added particularly to improve the physical stabilityof suspensions and valve performance. These include lecithins, disodiumdioctylsulphosuccinate, oleic acid and sorbitan esters. Cosolvents mayalso be added to improve solubility of surfactant in propellant ormodify the pharmacological performance. These include alcohols andglycols, e.g., ethanol, isopropylalcohol, glycerol, propylene glycol,polyethylene glycol, etc., or mixtures thereof. Further excipients maybe added to improve performance or taste, e.g., fatty acids and saltsthereof such as magnesium stearate, menthol oil etc.

Dry powder inhalers include devices which meter the drugs from a chamberwithin the device or those that deliver pre-metered doses utilizinggelatin, plastic or other capsules, cartridges, or blister packs and/orstrips.

Furthermore, the two active ingredients of the present compositions,i.e. compounds of Formula I and β₂ adrenergic agonists, may beadministered simultaneously, in a single dosage form, or-they may beseparately, but contemporaneously administered. As used herein,“contemporaneously” means that they are administered such that the peakserum levels of the two medicaments occur within four hours of oneanother. Usually, the closer to simultaneous peak serum levels, thebetter.

Compounds of Formula I as described above were tested in the followingassay for biological activity. The WI-38 human lung fibroblast line wasobtained from the ATCC (catalog number 75-CCL) and maintained in BasalMedium Eagle with Earle's salts (GibcoBRL product number 21010-046)supplemented with 2 mM glutamine and 10% fetal calf serum at 37° C. in a7% CO₂ (balance air), humidified atmosphere. One week before experimentswere done, the WI-38 cells were seeded into 48-well tissue culturedishes and maintained in media containing 10% fetal calf serum. Thecells were used when confluent. The day before the experiment the cellswere fed fresh media containing 10% fetal calf serum (0.25 mL per well).On the day of the experiment the media was removed from the cells and0.25 mL of media containing 5% fetal calf serum added.

The rat alveolar macrophage cell line RAW 264.7 was obtained from theATCC (catalog number 71-TIB) and maintained in Dulbecco's Modified EagleMedium (GibcoBRL product number 11960-044) supplemented with 2 mMglutamine, 1 mM sodium pyruvate and 10% fetal calf serum at 37° C. in a10% CO₂ (balance air), humidified atmosphere. One week beforeexperiments were done, the WI-38 cells were seeded into 48-well tissueculture dishes and maintained in media containing 10% fetal calf serum.The cells were used when confluent. The day before the experiment thecells were fed fresh media containing 10% fetal calf serum (0.25 mL perwell). One the day of the experiment the media was removed from thecells and 0.25 mL of media containing 5% fetal calf serum added.

To determine the IC₅₀ values for the compounds, 1 to 1000 dilutions weremade of the 5 mM stock solutions in DMSO to give 5 uM solutions. Thesesolutions were serially diluted 1:2 in DMSO to give a series of 12dilutions ranging from 5 uM to 2.4 nM. 0.0025 mL aliquots of the 12dilutions were added to wells of the WI-38 cells to give final compoundconcentrations ranging from 50 nM to 0.024 nM. The cells were stimulatedby addition of 0.001 mL of 0.025 ug/mL recombinant human Interleukin-1β(IL-1β-Calbiochem catalog number 407615) in 0.1% bovine serum albumin inphosphate buffered saline. The cells were incubated for 24 hours and thesupernatants harvested. The level of PGE₂ in the supernatants wasassayed using a commercial Enzyme Immuno Assay (EIA) kit (CaymanChemical catalog number 514010) after diluting 1:10 in EIA bufferaccording to the manufacturer's directions. The data from theseexperiments was fit to a 4 parameter logistic function using the IC₅₀routine in the Grafit 4 program (Erithecus software). IC₅₀ valuesdetermined in this manner were: budesonide 0.20 nM; budesonideisobutylcarbonate 0.12 nM; budesonide dodecylcarbonate 0.53 nM;budesonide hexylcarbonate 0.14 nM.

The compounds of Formula I were also tested in vivo in a rat paw edemamodel [Hirschelmann, R. and Bekemeier, H., Int J Tissue React 6, 471-475(1984)], which persons of skill in the art accept as predictive ofefficacy in treating asthma and rhinitis in humans.

Rat Paw Edema Protocol: Male Sprague Dawley rats Rj: SD (IOPS Han) (CEJ,France) weighing between 140 and 160 grams were used in the studies.Animals were housed in a temperature (19.5-24.5° C.), relative humidity(40-70%) and 12-hour light/dark cycle (light 6:00 a.m. to 6:00p.m.)-controlled room, with ad libitum access to filtered tap-water andstandard pelleted laboratory chow (U.A.R., France) throughout thestudies. Carrageenan lambda type IV (Sigma, France) was prepared as a 2%(w/v) solution in saline. Compounds to be tested were dissolved indimethylsulfoxide (DMSO) such that the indicated doses were in a finalvolume of 0.05 mL. Doses were expressed as mg/paw free active substance.From 17 to 19 hours before the studies the rats were fasted with freeaccess to water. The paw volumes of the left hindpaws of the rats weremeasured using an electronic plethysmometer type 7140 (Ugo Basile—Italy)at time=0. Paw edema was then induced by injection of 0.05 mL of 2%carrageenan solution into the left hindpaws of the rats. Immediatelyafter injection of the carrageenan, compounds in DMSO or vehicle alonewere injected into the same paw in a volume of 0.05 mL in a blind andrandom fashion.

The paw volumes were measured at 1.5 hours, 3 hours, 4.5 hours and 24hours after administration of the compounds. The edema volume of eachrat at each time point was expressed as the change from the initial pawvolume (time=0). A total of 5 rats were used for each compound dose andthe average edema volume calculated for each dose. The anti-inflammatoryeffect in treated groups was expressed as the percent inhibition ofedema volume compared to the vehicle-treated group at 1.5 hours, 3hours, 4.5 hours and 24 hours.

The results are shown in FIG. 1, in which the efficacies of equimolardoses (equivalent to 10 μg per paw of budesonide) are compared at 24hours. Budesonide itself reduces swelling by 46%. The formation of acarbonate ester at C21 decreases the efficacy of budesonide when theester is C₆ or smaller. Unexpectedly, at C₆ the curve reverses, and theefficacy increases. Thus, although one would expect C₇ to be lessefficacious than C₆, in fact it is surprisingly found more efficacious,and the C₁₀ carbonate is 30% more efficacious than budesonide itself.The correlation between numbers of carbons in the carbonate ester andefficacy reaches a peak at C₁₂ with an 88% reduction of swelling.

Other carbonates showed similar behavior. The phytol (Example 16) andfamesol (Example 17) carbonates exhibited normal onset of action andmaximum activity at 24 hours of 69 and 86 percent respectively. Theamine-terminal alkylcarbonate, Example 15, exhibited a maximum activityat 24 hours of 73 percent.

The enhanced effect of the carbonates and carbamates compared to theparent steroid is most dramatic at the 24-hour observation, as can beseen by comparing FIGS. 2 and 3, in which budesonide carbonate iscompared to budesonide.

1. A method of reducing edema, comprising: administering to a subject inneed an effective amount of a compound of Formula I:

wherein R¹ and R², independently for each occurrence, represent loweralkyl or lower acyl, or taken together R¹ and R² form a substituted orunsubstantiated ketal; R³is —OR⁴or —NR⁵R⁶; R⁴ is chosen from C₇ to C₂₄hydrocarbon, —(C₇ to C₂₄ hydrocarbon)—NR⁹R¹⁰; R⁵ is hydrogen or C₇ toC₂₄ hydrocarbon; R⁶ is chosen from C₇ to C₂₄ hydrocarbon and —(C₇ to C₂₄hydrocarbon)—COOH; R⁹ is hydrogen or C₁ to C₁₇ hydrocarbon; R¹⁰ ishydrogen or C₁ to C₁₇ hydrocarbon; R¹¹ is methyl or —OR²; and X and Yare independently hydrogen or halogen.
 2. A method according to claim 1,wherein the compound has formula:


3. A method according to claim 2, wherein the compound has formula:

wherein X is hydrogen or fluorine.
 4. A method according to claim 3,wherein the compound has formula

wherein R⁷ is hydrogen or lower alkyl; and R⁸ is lower alkyl.
 5. Amethod according to claim 1, wherein the compound has formula

wherein R⁴ is chosen from C₇ to C₂₄ hydrocarbon, —(C₇ to C₂₄hydrocarbon)—COOH, and—(C₇ to C₂₄ hydrocarbon)—NR⁹R¹⁰; R⁹ is hydrogen orC₁ to C₁₇ hydrocarbon; and R¹⁰ is hydrogen or C₁ to C₁₇ hydrocarbon. 6.A method according to claim 1, wherein in the compound of formula I, R⁴is C₇ to C₂₄ alkyl.
 7. A method according to claim 1, wherein thecompound has formula:


8. A method according to claim 7, wherein the compound has formula:


9. A method according to claim 8, wherein the compound has formula

wherein R⁷ is hydrogen or lower alkyl; and R⁸ is lower alkyl.
 10. Amethod according to claim 7, wherein the compound has formula

wherein R⁵is hydrogen or C₇ to C₂₄ hydrocarbon; and R⁶ is chosen from C₇to C₂₄ hydrocarbon and —(C₇ to C₂₄ hydrocarbon)—COOH.
 11. A methodaccording to claim 7, wherein in the compound R⁵ is hydrogen or loweralkyl.
 12. A method according to claim 7, wherein in the compound R⁶ isC₇ to C₂₄ alkyl.
 13. A method according to claim 3, wherein the compoundhas formula

and R⁴ is n-dodecyl.